CXCL12 and pulmonary fibrosis: Chemokines, such as CXCL12 (Antoniou et al. 2010; Chow et al. 2016), CCL1 (Liu et al. 2021), and CCL18 (Prasse et al. 2006), are implicated in pulmonary fibrosis, acting as chemoattractants by combining with the chemokine receptors, and yet the role of CXCL16 and its receptor remain poorly understood.